Engine starter



A. S. BOSMA ENGINE STARTER Feb. 22, 1938.

Filed March 6, 1957 2 Sheets-Sheet l :EEEIIIIHIIIIIIH.

INVENTOR I ALFRED S. BOSMA 2| ATTORNEYS Feb. 22, 1938. A s BOSMA 2,109,281

ENGINE STARTER Filed March 6, 1957 2 Sheets-Sheet 2 z 12 3 '6 r ;E V w Q 3 I :4 L i I 1 y.

i S i I I P42! 2O 26 /Z III,z.9 /111221;'cv IIIII/lI/IIIIIIIIIII/IA INVENTOR FIG. ALFRED S. BOSMA ATTORNEYS Patented Feb. 22, 1938 PATENT OFFICE ENGINE STARTER Alfred S. Bosma, New Holstein, Wis., assignor to The Lauson Company, New Holstein, Wis.

Application March 6, 1937,l Serial No. 129,401

4 Claims.

This invention appertains to starter attachments for internal combustion engines, and more particularly to a novel starter device operated by the manual depressing of a starter lever or treadie.

One of the primary objects of my invention is the provision of means whereby the starter is entirely disengaged from the starter pinion on the engine shaft on the return stroke of the starter to its original starting position.

Another salient object of my invention is the provision of a radial movable sector gear mounted on the oscillating arm of the starter, with automatic means for moving the sector gear into and out of engagement with the starter pinion according to the direction of movement of the oscillating arm.

A further important object of my invention is to provide an engine starter embodying a pedaloperated arm having a slidable sector gear mounted for free radial movement thereon, with means including a friction-operated finger for automatically moving the sector gear toward and away from the starting pinion on the crankshaft according to the direction of rotation of the arm.

A still further object of my invention is to provide a starter for internal combustion engines of the above character, which will be durable and efficient in use, one that will be simple and easy to manufacture, and one which can be placed upon the market and incorporated with an engine at a low cost.

With these and other objects in View the in- 35 vention consists in the novel construction, ar-

rangement, and formation of parts, as will be hereinafter more specifically described, claimed, and illustrated in the accompanying drawings, in which drawings:

Figure 1 is a top plan view of an internal combustion engine showing my improved starter incorporated therewith.

Figure 2 is a fragmentary, end elevational view of an internal combustion engine showing my improved starter attached thereto, with parts of the starter broken away and in section to illustrate structural details.

Figure 3 is an enlarged, detail sectional view through the starter, taken substantially on the 50 line 3-3 of Figure 2.

Figure 4 is a detail, fragmentary sectional view taken substantially on the line 44 of Figure 3, looking in the direction of the arrows, illustrating the means of frictionally mounting the friction finger on the supporting shaft of the starter.

Figure 5 is adetail perspective view of the sliding sector gear.

Figure 6 is a detail perspective view of one of the friction washers for'the friction finger.

Figure 7 is a detail perspective view of the friction finger.

Referring to the drawings in detail wherein similar reference characters designate corresponding parts throughout the several views, the letter E generally indicates: an internal combustion engine, which can be of any desired character or make, and S the novel starter therefor.

The engine E includes a crank-shaft l0 having rigidly mounted thereon a starter pinion ll. As the engine can be of any preferred'character', further description thereof is not deemed necessary.

My improved starter is arranged at one side of the engine and includes a stationary supporting shaft IZ eXtending in parallel relation to, but below, the crankshaft Ill. This shaft can be rigidly mounted in suitable brackets 13 secured to or formed on the crank-case M of the engine. Rotatably mounted on the shaft I2 in advance of the brackets I3 is a hollow shaft or sleeve I5. The inner end of this sleeve has rigidly secured thereto or formed thereon the upwardly extending treadle lever 16, and this treadle lever carries a suitable foot pedal I1. The forward end of the hollow shaft or sleeve I5 has formed thereon or rigidly secured thereto the starter arm 18, which extends toward the crank-shaft In. The outer end of the arm I8 is slotted, as at Hi, to form a guideway for slidably receiving the sector gear 20. This sector gear 20 is mounted for free radial movement on the arm, so that the same can move into and out of engagement with the pinion H, as will be hereinafter more specifically set forth.

A pair of spaced transversely extending pins 2| is carried by the arm l8, and these pins are mounted in angularly extending slots 22 formed in the sector gear. The inner edge of the sector gear also has formed therein a notch 23, the purpose of which will also be later set forth.

Cooperating with the sector gear 20 is a radially extending friction operated finger 24, and this finger is rotatably mounted on the reduced forward end 25 of the supporting shaft l2. The opposite faces of the friction finger 24 are engaged by friction Washers 26, and these washers have formed thereon inwardly extending tongues 21, which are slidably received within a key-way 28 formed in the shaft l2. The innermost friction washer 26 engages the shoulder on the shaft I2 formed by the reduced end 25 thereof. The washers are held on the reduced end of the shaft by means of a nut 29 threaded on said shaft, and, if desired, the nut can be locked on the shaft by means of a cotter key or the like 30. A resilient or spring washer 3| is placed on the reduced end of the shaft and engages the outermost friction washer 26, whereby a resilient pressure will be normally exerted on the friction washer; If desired, a wear washer 32 can be placed between the spring washer 3| and the inner face of the nut 29.

The operation of the starter is as follows:

When the foot pedal I! is depressed, the arm l8 moves upwardly and the sector gear 20 will be retarded by the finger 24. The sector gear 20 being retarded by the finger will be forced radially outward, due to the angularity of the two slots 22 working in engagement with the pins 2| on the arm l8. As the sector gear 2| is moved radially outward, its gear teeth will engage the pinion I on the crank-shaft of the engine, thereby revolving the engine shaft as the starter assembly is moved upward.

When the engine starts the pinion II on the crank-shaft being in engagement with the starter gear sector 20 will cause the sector to be carried upward faster than the arm |8 travels, and as a result the sector will be moved radially inward due to the engagement of the pins 2| with the walls of the angular slots 22.

If, however, the engine fails tostart, the arm I 8 and the sector gear 20 will travel upward to the end of the stroke, and as soon as the foot pedal I1 is released the contractile coil spring 33, connected at its opposite ends to the lever l6 and to the engine E, will function to move the lever, arm I8 and sector gear 20 to their original starting position. Upon this return movement the finger 24 will be retarded by the washers 26, and this finger will retard the downward travel of the sector gear 20.

As the travel of the arm I8 is now downward, the sector gear 20 is moved radially inward, due to the engagement of the pins 2| with the walls of the angular slots 22, thereby releasing engagement of the sector gearwith the pinion This allows the starter to move back into its original position for the next stroke, with the sector gear entirely out of engagement with the starter pinion. M

Changes in details may be made Without departing from the spirit or the scope of my invention, but what I claim as new is:

1. The combination with an internal combustion engine including a crank-shaft and a starter pinion thereon, of a starting device for the en gine including an oscillating starting arm, means for operating the arm, a sector gear slidably mounted on said arm for free radial movement toward and away from the pinion having angularly extending slots therein, stationary pins carried by the arm mounted in said slots for engaging the angular walls thereof, and means for initially retarding movement of the sector gear with the arm, as and for the purpose specified.

2. A starting device for internal combustion engines comprising an oscillating arm, a sector gear slidably mounted on the arm for free radial movement toward and away from the starter pinion of an internal combustion engine, means for operating the arm, said sector gear having angularly extending slots therein, transversely extending pins carried by the arm mounted in said slots for engaging the angular walls thereof, and means for automatically retarding initial movement of the sector gear with the arm upon movement of the arm in either direction.

3. A starting device for internal combustion engines comprising a stationary supporting shaft, a starter arm rotatably mounted on the shaft, means for swinging the arm in either direction, a sector gear slidably mounted on the outer end of the arm for free radial movement toward and away from the starter pinion of the engine, having inclined guide slots, pins carried by the arm extending through the slots for engaging the angular walls of said slots, a friction operated finger rotatably mounted on the shaft having engagement with the sector gear, and friction means on the stationary shaft for retarding movement of the finger, as and for the purpose specified.

4. A starting device for internal combustion engines comprising, a supporting shaft, a starter arm rotatably mounted on the shaft for movement in either direction, a guideway formed on the outer end of said arm, a sector gear received in said guideway for sliding movement having angularly extending slots, pins carried by the arm received in said slots for engagement with the angular walls thereof, the inner edge of said sector gear having a notch therein, a finger rotatably mounted on the shaft having its outer end received in the notch, friction washers engaging the opposite sides of the finger held against turning movement, and spring means normally urging the friction washers into binding contact with the finger, as and for the purpose specified.

ALFRED S. BOSMA. 

